Handling degraded conditions using a redirect module

Abstract

A method for execution by one or more processing modules of one or more computing devices of a dispersed storage network (DSN), the method begins by receiving a request sent to the DS processing unit while it is in a potentially degraded state. The method continues by processing (pre-processing) the request, sent to a DS processing unit, by a redirect module. The method continues by determining whether the DS processing unit is in a state where it can successfully complete the request (non-degraded). If the request is determined to not be able to be completed by the DS processing unit, then the method continues by the redirect module identifying another DS processing unit which can complete the request, and redirects the request to the another DS processing unit and if the DS processing unit is not in a degraded state and can complete the request itself, the redirect module transfers the request to the DS processing unit to be handled.

What is claimed is: 
     
       1. A method for execution by one or more processing modules of one or more computing devices of a dispersed storage network (DSN), the method comprises:
 receiving a request for data storage access sent to a first dispersed storage (DS) processing unit while it is in a potentially degraded state, wherein the first dispersed storage (DS) processing unit is remotely located from storage units of the DSN and operatively connected to the storage units through a communications network; 
 processing the request for data storage access sent to the first DS processing unit by a first redirect module of the DSN; 
 determining, by the first redirect module, whether the first DS processing unit is in a non-degraded state or degraded state; and 
 if the first DS processing unit is in the non-degraded state, transferring, by the first redirect module, the request for data storage access to the first DS processing unit to be processed; and 
 if the first DS processing unit is in the degraded state, identifying, by the first redirect module, a second DS processing unit that is in a non-degraded state, and redirecting the request for data storage access to the second DS processing unit; and 
 processing, by the second DS processing unit, the request for data storage access, wherein the processing includes one of: disperse error encoding segments of data from the request for data storage access, into one or more sets of encoded data slices and storing to a corresponding set of the storage units, or retrieving sets of encoded data slices of segments of the data, in the request for data storage access, from a corresponding set of storage units and thereafter disperse error decoding. 
 
     
     
       2. The method of  claim 1 , wherein the potentially degraded state occurs in any of: when the first or second DS processing unit is undergoing an update or upgrade; when the first or second DS processing unit is restarting its state; when the first or second DS processing unit is resetting its state; when the first or second DS processing unit suffers an irrecoverable fault; or when the first or second DS processing unit is initializing. 
     
     
       3. The method of  claim 1 , wherein the first redirect module tracks an internal state of the first or second DS processing unit, respectively, as well as another DS processing unit. 
     
     
       4. The method of  claim 1 , wherein, when the first or second DS processing unit is in the degraded state, the request for data storage access cannot be completed by the first or second DS processing unit, respectively. 
     
     
       5. The method of  claim 1 , wherein the degraded state is determined when the first or second DS processing unit is about to enter the degraded state. 
     
     
       6. The method of  claim 1 , wherein the first redirect module comprises a higher operational layer of the first or second DS processing unit, respectively. 
     
     
       7. The method of  claim 1 , wherein the first redirect module comprises a separate processing module from the first or second DS processing unit, respectively. 
     
     
       8. A method for execution by one or more processing modules of one or more computing devices of a dispersed storage network (DSN), the method comprises:
 receiving a request for data storage access sent to a first dispersed storage (DS) processing unit while it is in a potentially degraded state, wherein the first dispersed storage (DS) processing unit is remotely located from storage units of the DSN and operatively connected to the storage units through a communications network; 
 pre-processing, by a higher operational layer of the first DS processing unit, the request for data storage access sent to the first DS processing unit by determining, by a first redirect module, whether the first DS processing unit is in a non-degraded state or degraded state; and 
 if the first DS processing unit is in the non-degraded state, transferring, by the first redirect module, the request for data storage access to the first DS processing unit to be processed; and 
 if the first DS processing unit is in the degraded state, identifying a second DS processing unit that is in a non-degraded state, and redirecting, by the first redirect module, the request to the second DS processing unit; and 
 processing, by the second DS processing unit, the request for data storage access, wherein the processing includes one of: disperse error encoding segments of data from the request for data storage access, into one or more sets of encoded data slices and storing to a corresponding set of the storage units, or retrieving sets of encoded data slices of segments of the data, in the request for data storage access, from a corresponding set of storage units and thereafter disperse error decoding. 
 
     
     
       9. The method of  claim 8 , wherein the potentially degraded state occurs in any of: when the first or second DS processing unit is undergoing an update or upgrade; when the first or second DS processing unit is restarting its state; when the first or second DS processing unit is resetting its state; when the first or second DS processing unit suffers an irrecoverable fault; or when the first or second DS processing unit is initializing. 
     
     
       10. The method of  claim 8 , wherein the pre-processing determines an internal state of the first DS processing unit as well as the second DS processing unit. 
     
     
       11. The method of  claim 8 , wherein, when the first or second DS processing unit is in the degraded state, the request for data storage access cannot be completed by the first or second DS processing unit, respectively. 
     
     
       12. The method of  claim 8 , wherein the degraded state is determined when the first or second DS processing unit, respectively, is about to enter the degraded state.